That’s not true. The word “bug” has been used for problems in engineering well before computers; the funny story we all heard about a moth trapped in a relay causing a _bug_ in the Harvard Mark II is from 1947. Edison himself used the word back in 1878. The Wikipedia article about “Software bug” is pretty interesting: https://en.wikipedia.org/wiki/Software_bug#Etymology
For those interested Grace Hopper helped popularize this term
In 1946, when Hopper was released from active duty,
she joined the Harvard Faculty at the Computation
Laboratory where she continued her work on the Mark II
and Mark III. Operators traced an error in the Mark II
to a moth trapped in a relay, coining the term bug.
This bug was carefully removed and taped to the log
book. Stemming from the first bug, today we call
errors or glitches in a program a bug.